code: def time_lfilter(self, n_samples, numtaps):
      lfilter(self.coeff, 1.0, self.sig)
  
imports: import numpy
  import timeit
  from concurrent.futures import ThreadPoolExecutor, wait
  from .common import Benchmark, safe_import
label_desc: Use image node_id 2 for calling the Lfilter obj's underlying member method code with example usage: obj.time_lfilter(n_samples, numtaps) without return types